Fix typed select to propagate result type instead of Any#2698
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sumleo wants to merge 1 commit intoWebAssembly:mainfrom
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Fix typed select to propagate result type instead of Any#2698sumleo wants to merge 1 commit intoWebAssembly:mainfrom
sumleo wants to merge 1 commit intoWebAssembly:mainfrom
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In OnSelect(), when a typed select instruction has an explicit type annotation (non-empty expected vector), the code validates both operand types against expected[0] but never assigns the result_type. It remains Type::Any from initialization, so PushType(Type::Any) is called instead of pushing the declared result type. This violates the WebAssembly spec which requires a typed select to produce a value of the annotated type. The untyped select path already correctly sets result_type = type1; this commit applies the analogous fix for the typed path by setting result_type = expected[0].
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Closing as duplicate of #2707. |
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Summary
When processing a typed
selectinstruction (one with an explicit type annotation),TypeChecker::OnSelect()validates both operand types against the expected type but never assigns the validated type toresult_type. It stays asType::Anyfrom initialization, causingPushType(Type::Any)instead of pushing the declared result type.This violates the WebAssembly spec, which requires a typed select to produce a value of the annotated type on the value stack. The untyped select path already correctly sets
result_type = type1; this fix applies the analogous assignment for the typed path:result_type = expected[0].The Fix
A single line addition after the type checks in the typed select branch:
result_type = expected[0];This ensures the annotated type flows through to
PushType(result_type)andPrintStackIfFailed().Test plan